title: Diagnosis and surgical treatment of unilateral restrictive hypotropia and esotropia.
abstract: OBJECTIVE
  To describe the clinical features, radiological findings, and surgical treatment of patients with congenital unilateral restrictive hypotropia and esotropia.
  
  
  METHODS
  Retrospective analysis of patients presenting with unilateral restrictive hypotropia and esotropia. In all patients, magnetic resonance imaging (MRI) or computed tomography (CT) of the brain, brainstem, and orbits was obtained before surgery. Surgery consisted of inferior rectus recession combined in some cases with resection and upward transposition of the upper half of the horizontal rectus muscles. Minimum follow-up was 6 weeks.
  
  
  RESULTS
  Four patients meeting inclusion criteria were identified. All patients had amblyopia. Radiological findings included thickening of the posterior inferior rectus muscle belly (2 patients), inferior orbital fat hernia (2 patients), and an irregular soft tissue mass in the nasal inferior orbit (2 patients). The oculomotor nerve appeared to be normal in 3 patients and was not studied in 1. After surgery, 3 of 4 patients were aligned within 10Δ. One patient showed lower eyelid retraction and limitation of depression after a large recession of the inferior rectus muscle.
  
  
  CONCLUSIONS
  Unilateral hypotropia and esotropia can be associated with severe inferior rectus muscle restriction. Amblyopia may be common in these patients. Surgery to relieve the restriction can also correct the esotropia, suggesting a role for orbital connective tissue in the motility defect in these cases.
authors.affiliation: Beijing Children's Hospital Affiliated to Capital Medical University, Beijing, China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Lin
authors.forename: Fengyuan
authors.initials: F
authors.lastname: Man
authors.forename: Ningli
authors.initials: N
authors.lastname: Wang
authors.forename: Tao
authors.initials: T
authors.lastname: Chen
authors.forename: Gang
authors.initials: G
authors.lastname: Yu
authors.forename: Zhenchang
authors.initials: Z
authors.lastname: Wang
authors.forename: Qinglin
authors.initials: Q
authors.lastname: Chang
authors.forename: Yonghong
authors.initials: Y
authors.lastname: Jiao
authors.forename: Kanxing
authors.initials: K
authors.lastname: Zhao
mesh_terms: D000293:Adolescent; D000328:Adult; D001933:Brain Stem / Q000000981:diagnostic imaging; D002675:Child, Preschool; D004948:Esotropia / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery*; D005099:Exotropia / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D009801:Oculomotor Muscles / Q000473:pathology / Q000601:surgery; D013508:Ophthalmologic Surgical Procedures; D009915:Orbit / Q000000981:diagnostic imaging; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D015348:Vision, Binocular / Q000502:physiology; D014792:Visual Acuity / Q000502:physiology